$brand-primary: #8060ff;
$gray-dark: lighten(black, 25%);
$gray: lighten(black, 50%);
$white-faded: rgba(255, 255, 255, .7);
$black-faded: rgba(0, 0, 0, .8);
$gray-light: #eee;

.navbar-custom {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 3;
  font-family: 'Open Sans', 'Helvetica Neue', Helvetica, Arial, sans-serif;
  background-color: $white-faded;
  border-color: #e7e7e7;
  .navbar-brand {
    font-weight: 800;
  }
  .navbar-toggler {
    border-color: #bbb;
  }
  .navbar-nav{
    clear: both;

    .nav-item{
      float: none;
    }

    .nav-item + .nav-item{
      margin: 0;
    }
  }
  /* .{name}-transition vue transition setting */
  .navbar-nav.nav-expand-transition {
    transition: all .3s ease;
    overflow: hidden;
    height: 6rem;
  }
  /* .{name}-enter 定义进入的开始状态 */
  /* .{name}-leave 定义离开的结束状态 */
  .navbar-nav.nav-expand-enter, .navbar-nav.nav-expand-leave {
    height: 0; // 展开效果
    padding: 0 1rem; // 字插入效果
    opacity: 0; // 渐入效果
  }
  .nav-link {
    text-transform: uppercase;
    font-size: 12px;
    font-weight: 800;
    letter-spacing: 1px;
  }
  .nav-link.router-link-active{
    color: rgba(0,0,0,.6);
  }
  @media only screen and (min-width: 768px) {
    background: transparent;
    border-bottom: 1px solid transparent;
    padding: 0.75rem 1rem;

    .navbar-nav{
      clear: initial;
      display: flex;
      margin-top: 0.425rem;

      .nav-item + .nav-item{
        margin-left: 1rem;
      }
    }

    .navbar-nav.nav-expand-transition {
      height: inherit;
    }

    .navbar-brand, .navbar-nav .nav-link {
      color: white;

      &.router-link-active,
      &:hover,
      &:focus {
        color: $white-faded;
      }
    }
    .nav-item {
      color: white;

      &.router-link-active,
      &:hover,
      &:focus {
        background: transparent;
        color: $white-faded;
      }

      &::after{
        content: '';
        background-color: $white-faded;
        display: block;
        height: 2px;
        width: 100%;
        transform: scaleX(0);
        transition: all 0.2s ease-in-out;
      }

      &:hover::after{
        transform: scaleX(1);
      }
    }
    .nav-link {
      padding: 0.225rem 0;
    }

    transition: background-color 0.3s;
    /* Force Hardware Acceleration in WebKit */
    transform: translate3d(0, 0, 0);
    backface-visibility: hidden;
    &.is-fixed {
      /* when the user scrolls down, we hide the header right above the viewport */
      position: fixed;
      top: -61px;
      background-color: rgba(255, 255, 255, 0.9);
      border-bottom: 1px solid darken(white, 5%);
      transition: transform 0.3s;
      .navbar-brand, .nav-link {
        color: $gray-dark;

        &.router-link-active,
        &:hover,
        &:focus {
          color: $brand-primary;
        }
      }
      .nav-item::after{
        background-color: $brand-primary;
      }
    }
    &.is-visible {
      /* if the user changes the scrolling direction, we show the header */
      transform: translate3d(0, 100%, 0);
    }
  }
}